Re: Topband: Anybody?
Typically there are quite a few, and over time it would build up data points. Since WSPR is a weak signal mode, the antenna question is moot. A simple script might be able to be able to be written to either switch antennas at different transmission cycles, or to key different rigs. I like the idea of switching antennas as that takes the rig out of the possible variables - even though it is probably in the noise. -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Jim Brown Sent: Friday, January 01, 2016 1:50 PM To: topband@contesting.com Subject: Re: Topband: Anybody? On Fri,1/1/2016 10:04 AM, D. Scott MacKenzie wrote: > I like your RBN testing - nice idea. I wonder if the process could be > automated to some extent by using WSPR. By proper programing you > could alternate antennas. Might be an interesting to try. This way > you could let it run over a period of time, and collected. Data is > gathered in SNR and 6 digit grid. Data can then be analyzed and presented in a suitable format. Yes, with any evaluation of antenna performance, more data from more points over greater time is better. We did what we could easily do without that automation. I don't know enough about WSPR to know the extent to which two QRP rigs at the same site could TX with different callsigns in alternate transmission cycles. Another limitation is the number of WSPR stations active on 80M with antennas good enough to hear us. 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Anybody?
I like your RBN testing - nice idea. I wonder if the process could be automated to some extent by using WSPR. By proper programing you could alternate antennas. Might be an interesting to try. This way you could let it run over a period of time, and collected. Data is gathered in SNR and 6 digit grid. Data can then be analyzed and presented in a suitable format. I would try it but no antennas are up now nor will be for the foreseeable future. -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Jim Brown Sent: Friday, January 01, 2016 12:40 PM To: topband@contesting.com Subject: Re: Topband: Anybody? I can confirm Jim's experience that the Spiderbeam poles are NOT very robust, and are not sufficiently robust to be used in the manner Spiderbeam describes. We bought a 40 ft Spiderbeam pole to use as part of an 80M vertical for FD and county expeditions for the California QSO Party. The antenna worked fine -- until the wind blew and broke the Spiderbeam mast at the point of attachment to the rest of the antenna. The poles are advertised as being reinforced by crossed fibers; our pole was not, which is why it broke. The mechanical engineer for our antenna, Glen, W6GJB, is an M.E. by degree, and practices as an aeronautical engineer in the space program. He's quite familiar with materials and the stresses in a given design. He holds a dozen or so patents. I can also confirm that the antenna is NOT easy to erect, and for the same reason Jim cited -- the top wobbles around, generating lots of side stresses as it goes up, making it more difficult to raise. We needed five people, one on each guy, and two at the antenna base. Our antenna, and our experience, is described here. http://k9yc.com/80M-FDVertical.pdf We're very pleased with its performance and every aspect of its design other than the Spiderbeam pole. We tested the antenna over poor ground at Glen's QTH, and our FD and CQP sites also have poor ground. Over good ground, the advantage of this antenna over the reference inverted Vee would increase by 3-6 dB. 73, Jim K9YC On Fri,1/1/2016 9:13 AM, Jim Garland wrote: > I have the 26m (85.3 ft) Spiderbeam fiberglass vertical, with sixty > 30m radials on top of sandy desert soil. It uses four 7m top hat > wires, and is tuned to 1.820 MHz, where the VSWR is 1.47:1. I feed it > with about 300m of buried hardline. The assembly instructions are > clear and the antenna tuned to frequency very easily. It's a good > perfomer, although the radiatmg wire only extends up to about 24m . > > Structurally, the antenna is relatively light duty. It has four levels > of guy lines (16 guys total), the top two levels being 1 mm Kevlar and > very thin polypropylene fishing line attached to the top hat wires.. > The top few sections of mast resemble fishing poles and are very > flexible. The bottom section is roughly 6 inch OD and with the > supplied rubber cap fits tightly into standard PVC plumbing tubing. I > anchored a 1m length of the PVC into concrete and that made a dandy anchor point for the mast. > > The top hat is made of very thin wire with a low breaking strength. > Rodents ate through the Kevlar guys last year and toppled the antenna, > which broke into three pieces. I redid the guys, elevating the anchor > points, so don't expect that problem to recur. Don't be deceived by > the YouTube video showing the pole being raised by two people. When > the wire is attached to the pole, including the top hat wires, > erection for me has been a four hour job involving a minimum of six > people; four at each guy anchor and two to hoist the mast. The > slightest wind makes erection very difficult because slight flexing > prevents the nested sections from sliding. Last time I did this I > mounted a 12 foot long 4x4 post in concrete next to the pole with an > inexpensive hand winch to raise the sections. That helped a lot. I can send photos to anyone interested. > 73, > Jim W8ZR _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Fw: GAP VERTICAL QUESTION
Personally, I use an 80 M loop - I like it especially for stateside contest like Sweep or FD. Nice solid signal on 40M and 80M. It does much better than the Titan. But the Titan is much less maintenance and I don't have to put it up and rebuild it each year. With two hurricanes, no guying and no maintenance work at all, the antenna stays up, good SWR and I can make the occasional contact. Will I ever be the big dog - nope. I had a much better station in the mid-west, but we all make compromises,. -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Gary and Kathleen Pearse Sent: Wednesday, December 12, 2012 3:44 PM To: topband List Subject: Re: Topband: Fw: GAP VERTICAL QUESTION FWIW, at one point on a 5 acre remote parcel I had a GAP Voyager, GAP Titan, 80/160 parallel Inv-L over 120/125' radials, a 160M Inv-V, a F-12 C-4SXL beam at 54', and homemade vertical fan dipoles for 10-40M. Tall 70-85' trees that later burned in a forest fire held up the wires. The GAPS were just that...always at the bottom of the RF food chain. The vertical dipoles were down in strength from the F-12 beam some, yet I heard and worked everything the beam did when compared. They are a good alternative to a vert on the same band if supports are available. I had verts for 40 and 20 over a dense radial field (~60), but removed them when the vertical dipoles prevailed. The Inv-L worked all bands 10-160, with varying results depending on the other antennas and signal direction/time of day. I fed it with both coax plus RF chokes at both ends of the run, and twin-lead over the few years it was up. It was a full size vert on 80 due to a second wire parallel to the 160 L fed at the same point. The twin-lead fed Inv-V did the same for all bands, and had good gain on 10-40 off the ends. The Inv-L usually beat the Inv-V at the same height (~80') on 80-160. In my experience an Inv-L for 160 would be a good choice if one could only have one wire. Tuning is critical for multi-band ops. During this experiment I also had a 2-el horizontal loop for 80 at 55', which was excellent for NVIS and out to ~2500 miles from KL7, and a 1000' horizontal loop at 50-80', which was not worth the effort to build. Today, only the 80 loop and F-12 beam remain at that location. 73, Gary NL7Y ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
Re: Topband: GAP VERTICAL QUESTION
I have a Gap Titan. As the other people indicate it is not as good as a whole variety of other antennas. It is only good for 80 and up. I find that it works fairly well on 40 and 20M. Do I get stomped on in a pile-up - yes I do. Will I eventually make the contact - probably. At times my dipole on 40M does better, at other times it is the Gap Titan. However, I didn't buy this antenna to be the top of the pileup. I bought it to be maintenance free and a low hassle installation. It has been up for 10 years, and it has satisfied the goal of having an antenna in the air with very little maintenance. I make contacts when I want - I just wont be the first one to work the rare DX in a pileup. Scott aka kb0fhp -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of DGB Sent: Tuesday, December 11, 2012 6:27 PM To: topband@contesting.com Subject: Re: Topband: GAP VERTICAL QUESTION K7LXC book review was with the Titan. It was a poor performer against the Challenger, much less my other antennas IMHO of my testing between the two, Junk! de ns9i On 12/11/2012 5:13 PM, Tom W8JI wrote: So my question is does anyone have actual experience with these antennas (especially the voyager) as compared to other antennas for a specific frequency. Now guys .. I know you cant really compare a 6 element beam to a vertical of this kind but I am talking about a comparison that is realistic.. like how does it hear, tune, match get out compared to something like another vertical or a dipole up some reasonable distance. Jim, Years ago someone purchased and had me measure a GAP vertical. The Gap was terrible on 160 and 80 meters. It was OK on most other bands. On 160 meters, although I have a pretty good mobile antenna, I had about the same field strength from my mobile antenna. The Gap was down about 10 dB from a 1/4 wave on 80 meters, as I recall. My mobile antenna is about 20 dB down from my 1/4 wave 160 meter vertical. The ARRL reviewed one Gap vertical in an on-the-air A-B test, and a small ground mounted trap vertical was equal or better. I'm sure you can search ARRL reviews and find this review. Also, the HF Verticals test by K7LXC and Ward Silver compared many verticals, and had about the same results on 80 meters as I found and the ARRL found. All of these completely independent tests were A-B tests against other reference verticals, and all pretty much agreed with each other. This doesn't mean you can't work DX with a Gap, because I can work VK, JA, and Europe on 160 with my mobile antenna. I've worked several Europeans on 160 SSB while driving down the highway. I can, at times, even beat others in pileups from the mobile on 80 meters. Obviously if the Gap is as good as a better mobile antenna, you can probably work a lot of DX with it. 73 Tom ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com ___ Topband reflector - topband@contesting.com
